Calibration Overview
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Traceable Transmission Electron Microscopy Calibration Standard

Kikuchi pattern of single crystal silicon Kikuchi pattern of single crystal silicon viewed down the <011> zone axis. The broad band in the center of this figure is between the [200] Kikuchi lines.
This standard is directly traceable to the crystal lattice constant of silicon and performs all major instrument calibrations for Transmission Electron Microscopy:
  • All TEM magnification ranges
  • Camera constant
  • Image/diffraction pattern rotation

MAG*I*CAL consists of an electron transparent cross-sectional TEM sample made from a MBE grown, single-crystal semiconductor wafer. When the calibration structure is viewed in a TEM, it appears as a series of light and dark layers where the layer thicknesses are accurately known.
The calibration thickness measurements of the light (silicon) and dark (SiGe alloy) layers are based on careful TEM measurements of the <1 1 1> lattice spacing of silicon, which is visible on the calibration sample itself and are supported by X-ray diffraction measurements.
The layer spacings are designed so the sample can be used to calibrate the entire magnification range in TEM from 1,000X to 1,000,000X. As the sample is also a single crystal of silicon, the calibrations requiring electron diffraction information, such as the camera constant and image/diffraction pattern rotation, can also be performed easily and unambiguously.
The MAG*I*CAL calibration sample is directly traceable to the lattice constant of silicon <1 1 1> (0.3135428nm). This constant can be measured directly on the MAGICAL sample, providing unbroken traceability to a fundamental constant of nature. One single calibration sample can be used to provide all three of the major TEM instrument calibrations at all magnifications and all cameras lengths.

Layer Thickness Values
Calibrated Values = +/- 1.4%

Surfacemagical calibration values

To improve accuracy when making measurements, always measure the largest distance clearly visible on the micrograph. For example, at the highest magnification ranges, measure the distance across the entire set of five dark layers and four light layers, instead of trying to measure an individual dark layer.

magical grid Diagram of the MAG*I*CAL® grid. The arrows point to the four regions containing the calibration marks.
magical kikuchi pattern A Kikuchi pattern from the single crystal sample which can be used to align the sample.
magical micrograph An optical micrograph of the colors of silicon when it is thinned down to TEM thicknesses, the 1mm central perforation, and the four areas containing the calibration markings (arrows).
lattice image of the single crystal silicon A lattice image of the single crystal silicon sample. The silicon <1 1 1> lattice planes should be measured perpendicular to the planes, in the direction of the arrow.

Prod # Description Unit Price Order / Quote
675 MAG*I*CAL® Calibration Standard each $1540.00